The formation and stability of junctions in single-wall carbon nanotubes.
Nanotechnology
; 29(48): 485702, 2018 Nov 30.
Article
in En
| MEDLINE
| ID: mdl-30207298
ABSTRACT
The structure and stability of molecular junctions, which connect two single-wall carbon nanotubes (SWCNTs) of different diameters and chiral angles, (n 1, m 1)-(n 2, m 2), are systematically investigated by density functional tight binding calculations. More than 100 junctions, which connect well-aligned SWCNTs, were constructed and calculated. For a highly stable junction between two chiral (n 1, m 1) and (n 2, m 2) SWCNTs with opposite handedness, the number of pentagon-heptagon (5/7) pairs required to build the junction can be denoted as â£â£n 2 - n 1⣠- â£m 2 - m 1â£â£+min{â£n 2 - n 1â£, â£m 2 - m 1â£} with (n 2, m 2) rotating π/3 angle or not. While for a junction connected by two zigzag, armchair or two chiral SWCNTs with the same handedness, the number of 5/7 pairs is equal to â£n 1 - n 2⣠+ â£m 1 - m 2â£. Similar to the formation energies of grain boundaries in graphene, the curve of the formation energies vs. chiral angle difference present an 'M' shape indicating the preference of â¼30 degree junctions. Moreover, the formation energies of the zigzag-type and armchair-type junctions with zero misorientation angles are largely sensitive to the diameter difference of two sub-SWCNTs.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Language:
En
Journal:
Nanotechnology
Year:
2018
Document type:
Article